Camera control apparatus and method

ABSTRACT

A current image-sensing area of a camera is displayed as a first frame, and a potential image-sensing area obtainable by panning/tilting the camera at an image-sensing magnification is displayed as a second frame. To control panning/tilting of the camera, a display position of the second frame is changed, and in accordance with the changed display position, control data is transferred to the camera.

BACKGROUND OF THE INVENTION

This invention relates to a camera control apparatus and, moreparticularly to a camera control apparatus and method which controlsimage-sensing direction (panning/tilting) and image-sensingmagnification (zooming).

Conventionally, as a means to remote-control panning/tilting and zoomingof a video camera, operation levers, a joy stick, push-button switchescorresponding to two-axial rotation or display of such tools with apointing device such as a mouse, are known. For example, a rotationangle or angular velocity is controlled by a lever angle, or rotation inan upward/downward/rightward/leftward direction is made by a buttonbeing pressed. Similarly, zoom control is made by using a button fordesignating a wide-end (pantoscope) position or a tele-end (telescope)position.

With the camera operation means or control device, a camera ispanned/tilted in accordance with operation of the pan/tilt control. Thisis suitable for operation while observing a monitor screen image;however, it is not convenient when moving to a target position is awayfrom the current camera position.

To solve this problem, a controller can be provided to directly inputrespective pan and tilt angles as numerical values. The controllerdetermines movement of the camera to the target positions. However, inthis case, an operator cannot intuitively determine an area within apanning/tilting range, i.e., an image area which comes into animage-sensing view.

SUMMARY OF THE INVENTION

The present invention has been made in consideration of the abovesituation, and has its object to provide a camera control apparatuswhich solves the above problems.

Accordingly, an object of the present invention is to provide a cameracontrol apparatus which can simply and quickly control a camera to atarget regardless of current pointing position of the camera.

Another object of the present invention is to provide a camera controlapparatus which accurately presents an operator an image-sensing view tobe obtained, upon control to target status.

According to the present invention, the foregoing object is attained bydisplaying a first frame indicating a maximum image-sensing area,defined by limitation of image-sensing directions and a second framewithin the first frame, indicating an current image-sensing area. Thesecond frame is displayed at a fixed position, and a display positionand a display size of the first frame are changeable such that those ofthe second frame correspond to a current image-sensing direction andimage-sensing magnification with respect to the first frame. Thus,zooming is more similar to human action to move closer to an object soas to enlarge the object in his/her sight. This assists the operator tomake more intuitive operation.

Further, as the panning/tilting and zooming of the camera can becontrolled by operating the first frame, operability is greatlyimproved.

Further, as an object within the maximum image-sensing area is sensed inadvance and displayed within the first frame, a portion of the object tobe image-sensed can be more accurately selected. Thus, thepanning/tilting and zooming of camera can be controlled with appropriatevalues.

Other objects and advantages besides those discussed above shall beapparent to those skilled in the art from the description of a preferredembodiment of the invention which follows. In the description, referenceis made to accompanying drawings, which form a part thereof, and whichillustrate an example of the invention. Such example, however, is notexhaustive of the various embodiments of the invention, and thereforereference is made to the claims which follow the description fordetermining the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate embodiments of the invention and,together with the description, serve to explain the principles of theinvention.

FIG. 1 is a block diagram schematically showing a construction of afirst embodiment of the present invention;

FIG. 2 is a schematic view showing basic display elements on a displaydevice 22 of the first embodiment;

FIG. 3 is a display example on the display device 22 of the firstembodiment;

FIGS. 4A and 4B are display examples on the display device 22 of firstembodiment;

FIG. 5 is a flowchart showing a main routine according to the firstembodiment;

FIG. 6 is a flowchart showing in detail processing at step S1 in FIG. 5;

FIG. 7 is a flowchart showing in detail processing at step S2 in FIG. 5;

FIG. 8 is a flowchart showing in detail processing at step S3 in FIG. 5;

FIG. 9 is a modification example of the main routine;

FIG. 10 is another modification example of the main routine;

FIG. 11 is an explanatory view showing pan/tilt and zoom operation areasoverlaid on a frame 42;

FIG. 12 is an explanatory view showing the relation between anwide-angle image and the frame 42;

FIG. 13 is a flowchart showing processing at step S41 in FIG. 9;

FIG. 14 is a display example according to a second embodiment;

FIG. 15 is a display example according to a second embodiment;

FIG. 16 is a flowchart showing in detail processing at step S2 in FIG.5, according to the second embodiment;

FIG. 17 is a flowchart showing in detail processing at step S3 in FIG.5, according to the second embodiment; and

FIG. 18 is an explanatory view showing the relation between a wide-angleimage and the frame 42 according to the second embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention will now be described indetail in accordance with the accompanying drawings.

[First Embodiment]

FIG. 1 is a block diagram schematically showing a construction of afirst embodiment of the present invention. In FIG. 1, reference numeral10 denotes a video camera in which panning/tilting and zooming can becontrolled; 20, a camera controller, according to the presentembodiment, which controls the video camera 10; 22, a display devicewhich displays a potential maximum image-sensing area of the videocamera 10 and an image-sensing area based on current pan/tilt (panand/or tilt) and zoom values or control values; 24, a sensing-directiondesignator which designates a target image-sensing direction; 26, a zoomdesignator which designates a zoom value in the target image-sensingdirection; 28, a determination unit which determines input of newimage-sensing area; 29, an update designator which designates to updatea sensed image within the potential maximum image-sensing area; 30, anI/F (interface) unit for the video camera 10; 32, a CPU which controlsthe overall camera controller 20; and 34, a memory unit for storingcontrol programs of the CPU 32, control variables, current and maximumpan/tilt and zoom values, and the like. The I/F unit 30 and the camera10 are connected via a network cable, a communication line or the like.

FIG. 2 is a schematic view showing basic display elements on a displaydevice 22 of the first embodiment. The camera controller 20 of thepresent embodiment is constructed as, e.g., a part of a work stationused as a terminal of a teleconference system. One window of a monitorscreen image displayed at the work station functions as a display imageon the display device 22.

In FIG. 2, a rectangular frame 42 indicates a maximum image-sensing areacorresponding to maximum view of the camera 10 in a case where pan/tiltvalues are varied with a current zoom value.

A frame 44 indicates a current image-sensing area. The centralcoordinate position of the image-sensing area is fixed with respect to awindow 46. In this embodiment, the center of the frame 44 coincides withthe center of the window 46. Note that in this embodiment, the window 46is larger than the frame 42, however, this is made to assistunderstanding of the embodiment and the size of the window 46 is notnecessarily larger than the frame 42. The frame 42 can be larger thanthe window 46, so far as the frame 42 can be moved in the window 46 byvertically and horizontally scrolling information displayed within thewindow 46 with a slider (scroll) bar or the like. Although the frame 44is displayed at a fixed position and in a fixed size with respect to thewindow 46, if the window 46 is moved within the display screen image,the frame 44 moves following the movement of the window 46.

A frame 48 represents maximum coordinates from the center of the frame44 within the frame 42, obtained on the assumption that the frame 42 ismoved to the pan and tilt maximum values (actually, the display positionand size of the frame 42 are changed, as described later). The sizes ofthe frames 42 and 48 change in proportion to a zoom value.

Note that the value of status at the minimum zoom ratio (magnification)will be referred to as "zoom value 1", and that at the maximum zoomratio (tele-end zooming (with the longest focal distance)), "zoom value3".

FIG. 3 is a display example of the window 46 when the camera, having amaximum pan angle from -80° to +80°, a maximum tilt angle from -50° to+50°, and zoom values 1 to 3, is set at a pan angle 20° and tilt angle20°. In FIG. 3, a frame 43 indicates a potential maximum image-sensingarea at the zoom value 1; and a frame 45 represents a potential maximumimage-sensing area at the zoom value 3. A frame 47 represents maximumcoordinates from the center of the frame 44 obtained within the frame 43on the assumption that the frame 44 of the current image-sensing area ismoved to maximum pan and tilt values. Similarly, a frame 49 representsmaximum coordinates from the center of the frame 44 obtained within theframe 45 on the assumption that the frame 44 is moved to the maximum panand tilt values.

Although the pair of frames 45 and 49 and the pair of frames 43 and 47are both displayed in FIG. 3, actually, only one of these pair isdisplayed. That is, the frame 44 indicating a current image-sensing areaand a frame indicating a potential range (frame 45 or 43) and a maximumrange from the center of the frame 44 (frame 49 or 47) at a zoom valueat that time are displayed.

FIG. 4A is a display example of the window 46 when a camera, having amaximum pan angle from -80° to +80°, a maximum tilt angle from -50° to+50°, and zoom values 1 to 3, is set at a pan angle -80°, tilt angle 0°and the zoom value 1 (minimum zoom ratio). FIG. 4B is a display exampleof the window 46 when the camera is set at the same pan angle, the sametilt angle and the zoom value 3 (maximum zoom ratio).

In FIG. 4A, the area of the frame 44 of the current setting has thepotential maximum area 43 at the zoom value 1 and has a larger potentialmaximum area 45 in FIG. 4B at the zoom value 3. That is, when amagnification is large, a view angle is small, while the magnificationis small, the view angle is large.

Next, the operation of the present embodiment will be described withreference to FIGS. 5 to 8. FIG. 5 shows a main routine of the operationof the present embodiment. In this routine, processing at thesensing-direction designator 24 (S1), processing at the zoom designator26 (S2) and processing at the determination unit 28 (S3) aresequentially performed. After the processing at the determination unit28 (S3), if target pan/tilt and zoom values have been determined (S4),as designation of a new image-sensing area has been completed, the videocamera 10 is controlled to a pan/ tilt and a zoom values correspondingto the target values (S5). If target values have not been determined(S4), steps S1 to S3 are repeated.

FIG. 6 is a flowchart showing in detail processing at step S1 in FIG. 5.The present embodiment employs a pointing device (mouse in thisembodiment) as the sensing-direction designator 24, and designates a newposition of the frame 42 by operating (dragging) the pointing device.

More specifically, it is first determined whether or not there has beeninput at the sensing-direction designator 24 (S11). The "input" meansthat a mouse is moved while a mouse button is pressed, when a cursor isdisplayed on the frame 42. At this time, the frame 48 movescorresponding to the operation of the mouse. If it is determined thatthere has not been input at the sensing-direction designator 24 (S11),i.e., the mouse button has not been pressed, the processing in FIG. 6ends, and moves to step S2 of the main routine in FIG. 5. If the mousehas been moved (S11), it is determined whether or not the center of theframe 44 is without an area corresponding to the moving frame 48 (S12).If Yes, the process returns to step S11; while if NO, pan/tilt valuesstored in the memory unit 34 are set to values corresponding to the newposition of the frame 42. Further, the frames 42 and 48 are displayed atthe new positions (S13).

FIG. 7 is a flowchart showing in detail processing at step S2 in FIG. 5.The present embodiment employs specific key (e.g., an UP/DOWN key ofzooming level) or a similar button on a graphical user interface (GUI)as the zoom designator 26.

First, it is determined whether or not there has been input at the zoomdesignator 26 (S21). If NO, the processing in FIG. 7 ends, and moves tostep S3 of the main routine in FIG. 5. If YES (S21), it is determinedwhether or not zoom amount exceeds the zoom allowable range (S22). IfYES, the process returns to step S21; while if NO, the zoom value storedin the memory unit 34 is updated to the new value corresponding to theinput at the zoom designator 26. Further, on the display screen of thedisplay device 22, the frames 42 and 48 are displayed in sizes and atpositions corresponding to the new zoom value (S23).

FIG. 8 is a flowchart showing in detail processing at step S3 in FIG. 5.The present embodiment employs a specific key (e.g., an ENTER key) or asimilar button on a GUI as the determination unit 28. First, it isdetermined whether or not there has been an input at the determinationunit 28 (S31). If NO, the pan/tilt and zoom values stored in the memoryunit 34 are outputted for other processing, and the process ends (S32).

If determination of input has been made at the determination unit 28,respective pan, tilt and zoom control amounts are calculated based onvalues stored in the memory unit 34 at that time, and the obtainedvalues are transmitted to the video camera 10.

A video image image-sensed by the video camera 10 is displayed in avideo-display window provided at other clients on the network, ordisplayed in a video display window (not shown) provided on the screenof the display device 22 via the I/F unit 30.

In the main routine according to the present embodiment, inputs at therespective devices 24, 26 and 28 are sequentially checked by a pollingmethod, however, the processing at the respective devices 24, 26 and 28can be implemented as interrupt processing or a procedure called fromGUI.

Further, specific key-input is considered as input at the zoomdesignator 26, however, it may be arranged such that a pointing devicesuch as a mouse be used to designate zooming by moving a specificcontrol point displayed on the frame 42, as in a graphic software.Further, panning/tilting and zooming can be integrally designated bymoving a frame and expanding/reducing the frame, as in graphic software.

In the present embodiment, the video camera 10 is controlled inaccordance with determination of new designation of the frame 42 (S5 inFIG. 5). However, it may be arranged such that when any of pan/tilt andzoom values is changed, the camera 10 is controlled in correspondencewith the value immediately. It is possible to select one of thesemethods as operation mode.

In a case where data transfer between the video camera 10 and thecontroller 20 is made at high speed, it is desirable to real-timetransfer the result of operation with respect to the frame 42 to thevideo camera 10 without designation from the determination unit 28,since real-time control is possible.

Contrary, if the data-transfer speed is relatively low, upon operationsuch as moving with respect to frame 42, as a control signal istransferred at each operation step, response becomes slow. Accordingly,if the data-transfer speed is relatively low, it is preferable totransfer control data to the video camera 10 after designation at thedetermination unit 28 has been confirmed, as described above.

The camera controller 20 first detects a data-transfer speed between thevideo camera 10, and automatically changes the data-transfer speed. Todetect a data-transfer speed, the camera controller 20 may transfer anappropriate control signal (data) to the video camera 10 and receivesacknowledgment from the video camera 10 so that the data-transfer speedcan be determined from time delay.

Next, immediate control of the video camera 10 in case of change in pan,tilt and zoom values has occurred will be described.

FIG. 11 shows, with different hatched areas with respect to the frame 42(FIG. 2) showing an image-sensing area at a current zoom value, threeareas 50, 52 and 54. That is, the areas 50 are overlapped at the fourcorners of the frame 42 by areas 52, the area 52 extends along the fourends of the frame 42, and the area 54 is an area obtained by removingthe area 44 from the residual area within the area 42. These areas 50,52 and 54 are operation areas respectively for panning, tilting andzooming.

The area 54 is employed for panning/tilting. When the mouse cursor ismoved into the area 54, the mouse cursor is transformed into an icon("hand" in FIG. 11) indicative of pan and/or tilt operation. When thisicon is dragged, the CPU 32 updates the position of the frame 42 to aposition moved by direction of the movement and corresponding amount, incorrespondence with this operation, further, the CPU 32 pans/tilts thevideo camera 10 by corresponding angle(s). FIG. 11 shows an examplewhere the mouse cursor ("hand" icon) is moved diagonally left-upward. Asit is well known, drag operation is completed when the mouse button isreleased, then the pan/tilt operation is completed.

If the camera controller 20 has a high processing performance and a highdata transfer speed, it can rotate-control the video camera 10 followingthe drag operation. If the camera controller 20 has a low processingperformance, it only updates the position of the frame 42 during thedrag operation, and it rotate-controls the video camera 10 after thecompletion of drag operation.

The areas 50 and 52 are employed for zooming. When the mouse cursor ismoved into the area 50 or 52, the mouse cursor is transformed into anicon ("double-headed arrow" indicating expansion/reduction of the frame42 in FIG. 11) indicative of zoom operation. When this icon is draggedwhile the mouse button is pressed, the CPU 32 updates the size of theframe 42 in correspondence with a movement amount toward inside/outsideof the frame 42, further, the CPU 32 controls the video camera 10 withthe new zoom value. The drag operation is completed when the mousebutton is released, and the zoom operation is completed. In zoomoperation, zoom control of the video camera 10 following drag operationis performed depending upon the processing performance and thedata-transfer speed of the camera controller 20.

[Modification]

FIG. 9 shows a modification to the main routine in FIG. 5. In FIG. 9, atstep S41, a plurality of views (i.e., an image within a potentialmaximum view) obtained whenever change of panning/tilting at the zoomvalue 1 (wide-end zooming) are linked and displayed within the frame 42.

First, at the zoom value 1, the video camera 10 is controlled to obtainpartial video images within the potential maximum image-sensing area,and the partial video images are transferred. The partial video imagesare received and stored as respective image data into the memory unit,for example, and image data representing one large image is generated bylinking the stored respective image data. Thereafter, in the image datarepresenting the one large image, image data corresponding to an areabased on a zoom value before the current processing is extracted, andthrough predetermined processing, displayed within the frame 42. As theprocessing upon displaying the data within the frame 42, well-knownthinning and interpolation methods used in image expansion/reduction areemployed.

FIG. 12 is an explanatory view showing relation between an wide-angleimage and the frame 42, for more detailed explanation. In FIG. 12,numeral 100 denotes an image generated by linking images obtained fromsequential pan/tilt controls. Numeral 100 also denotes an area to bedisplayed within the frame 42 at the zoom value 1. Numeral 101 denotesan area to be displayed within the frame 42 at the zoom value 2; and102, an area to be displayed within the frame 42 at the zoom value 3.

Thus, the area displayed within the frame 42 changes in accordance withzoom value, since the actual position and size of the image-sensing area44 of the video camera 10 are fixed. Note that the positions and sizesof the areas 100 to 102 are calculated based on the zoom value, however,it may be arranged such that a table having zoom values, extractedpositions and sizes is prepared in advance and the positions and sizesof these areas are obtained by utilizing the table.

The above processing is implemented in accordance with a procedure asshown in FIG. 13.

At step S130, current angle information, i.e., a pan angle, a tilt angleand a zoom value are saved. At step S131, the zoom value 1 is set. Atstep S132, the pan angle and the tilt angle are newly set, and at stepS133, request for taking a picture is made. At step S134, video data(image data) is received from the video camera 10, and the received datais stored into the memory unit 34. At step S135, it is determinedwhether or not all the image data of necessary partial images togenerate an image corresponding to the area 100 (FIG. 12) have beenobtained. If NO, the process returns to step S132, to perform imagesensing at other angles.

Thus, as all the image data of necessary images to generate an image tobe displayed in the frame 42 have been obtained, the process proceeds tostep S136, at which the respective image data are linked, and one imagedata corresponding to the area 100 is generated.

Thereafter, the process proceeds to step S137, at which the saved angleinformation is restored. At step S138, an image within an area (any ofareas 100 to 102) of a size based on the restored zoom value isextracted, and image processing such as thinning or interpolation isperformed on the image so as to be adjusted to the size of the frame 42at the zoom value.

As image data to be displayed within the frame 42 has been generated,the image is displayed within the frame 42 (and 48) at step S139. Atstep S140, the frame 44 is displayed.

Thus, as an image around the frame 44, i.e., a current image-sensingarea can be displayed within the frame 42, an operator can see object(s)or person(s) around the frame 44.

The processing at step S41 in FIG. 9 is as described above. Next,processing at step S42 will be described below.

Similar to FIG. 5, the processing at the sensing-direction designator 24(S42) and the processing at the zoom designator 26 (S43) are called.Note that if the zoom value is changed by the zoom designator 26, theimage to be displayed within the frame 42 is changed. In this case,within the one image data in the memory unit 34, an area based on thechanged zoom value is extracted, and after predetermined processing, animage of the extracted area is displayed within the frame 42.

If there has been a requirement to update the maximum range image at theupdate designator 29 (S44), the image to be displayed within the frame42 is updated (S45). This step S45 is the same as previously describedstep S41. That is, zooming is set to a tele-end zooming, image sensingis sequentially made while panning/tilting from one end to the other endof the pan/tilt range. The obtained image data is stored into the memoryunit 34, and an image is displayed in the size of the frame 42. Then,the processing at the determination unit 28 is called (S46), and ifinput of camera control has been determined (S47), pan/tilt and zoomcontrols are made based on set values corresponding to a new position ofthe frame 44 (S48).

As the maximum image-sensing area image displayed within the frame 42 isobtained by linking a plurality of sensed images, it has distortions atjoint portions. However, such distortions do not damage the advantageouspoints in operation of the present embodiment. Further, the updaterequirement (S44) is not limited to operation of the update designator29. For example, the update requirement may be a plurality of specificoperations. Furthermore, a currently-sensed image may be displayedwithin the frame 42.

FIG. 10 is another modification to the main routine where acurrently-sensed image is displayed within the frame 42. After thecamera control (S48), an image sensed by the video camera 10 is pickedup. In the maximum view image stored in the memory unit 34 at step S45,an area corresponding to the frame 44 is updated using this image, i.e.,the currently-sensed image. Thereafter, the maximum view image withinthe frame 42 is updated (S49).

This enables the operator to confirm which image portion in the maximumview image is actually image-sensed, and to easily judge to what levelspanning/tilting and zooming are adjusted. Note that in the presentembodiment, the window 46 has a fixed size which is larger than themovable area of the frame 42, however, the size of the window 46 may bevariable. In this case, when the size of the window 46 is smaller, apart of the image can be displayed with a tool such as a slider bar. Itis apparent that in this case, operation by GUI is partially limited.

As it is easily understood from the above description, the presentembodiment can change frame size upon zooming, thus attains a naturalway of display.

Further, pan/tilt and zoom statuses within a controllable range can beeasily obtained, which enables the operator to quickly control the videocamera with arbitrary control values. Further, as a maximumimage-sensing area image is picked up and displayed within acorresponding frame, upon operating the video camera, the operator cansee object(s) within an image-sensing area, which assists the operatorto operate the video camera and improves operability.

[Second Embodiment]

Upon pan/tilt operation, the first embodiment displays the frame 44indicating image-sensing area of the video camera 10 at a fixedposition, and displays the frame 42, indicating a potential maximumimage-sensing area by panning/tilting at a current zoom value. Thepanning/tilting of the video camera 10 is controlled by moving frame 42within the window 46. When the zoom value is changed, the size of theframe 42 is changed so as to clarify the relativity between the frames42 and 44.

In a second embodiment, panning/tilting is controlled by moving theframe 42, similar to the first embodiment. However, in this embodiment,the size of the frame 42 is not changed upon changing a zoom value, butthe size of the frame 44, i.e., the frame corresponding to a boundary ofa current image-sensing view of the video camera 10 is changed.

In the following description, elements corresponding to those in thefirst embodiment have the same reference numerals and the explanation ofthe elements will be omitted. Also, the construction of the apparatus isthe same as that of the first embodiment and the explanation of theconstruction will be omitted. Note that similar to the first embodiment,a live video image displayed within the frame 44 is displayed by anotherwindow.

FIGS. 14 and 15 are display statuses in the window 46 according to thesecond embodiment. FIG. 14 is a display example at the zoom value 3(tele-end zooming); FIG. 15 is a display example at the zoom value 1(wide-end zooming). As shown in these figures, the size of the frame 44is changed in accordance with zoom value, but the size of the frame 42is fixed regardless of the zoom value.

Similar to the first embodiment, the center of the frame 44 is fixed,and the frame 42 is movable.

As the frame 42 has a fixed size, a maximum movable range of the frame42 is determined. A frame 40 indicates the maximum movable range of theframe 42. This enables the operator to see limitations of movement ofthe frame 42.

The processing procedures according to the second embodiment are similarto those described in FIGS. 5 to 8 or FIGS. 9 and 10, except theprocessing in FIG. 7 and that in FIG. 8 are changed as follows.

First, processing of 48 indicating zoom instruction from the zoomdesignator 26 will be described with reference to the flowchart of FIG.16.

At step S21, it is determined whether or not there has been input at thezoom designator 26. If YES, the process proceeds to step S22, at whichit is determined whether or not the amount of control exceeds anoperation allowable range. If YES, the process returns to step S21.

On the other hand, if the zooming does not exceed the allowable range,the process proceeds to step S23', at which the zoom value is updated,the size of the frame 44 is determined based on the updated zoom value,and the frame 44 is displayed in the determined size. At this time, thesize of the frame 48 from the center of image-sensing area is alsoupdated.

In a case where there has been input at the determination unit 28,processing as shown in FIG. 17 is made.

First, at step S31, it is determined whether or not specific key-inputhas occurred at the determination unit 28 (e.g., manipulation of anENTER key) or similar button manipulation on GUI) has been made. If YES,the process proceeds to step S32', at which control data (or signal)based on the position of the frame 42 and a zoom value of the frame 44are outputted to the video camera 10.

Further, processing to display a potential image based on a current zoomvalue within the frame 42, i.e., the processing shown in FIG. 9 and thatin FIG. 10 are substantially the same. Difference is that the size ofthe frame 42 is fixed and the size of the frame 44 changes based on thezoom value.

Accordingly, at steps S41 and S45 in FIG. 9 and FIG. 10, the image afterzooming is fixed, as shown in FIG. 18.

Note that the processing at the other steps such as movement of theframe 42 are the same as those of the first embodiment, the explanationof the these steps will be omitted.

In the first and second embodiment, the size of the window 46 is fixed,however, it may be variable. In this case, the inside of the window 46can be scrolled with scroll bars, otherwise, the sizes of the frames 42and 44 can be changed in accordance with the size of the window 46.

As described above, the second embodiment enables the operator to easilydetermine panning, tilting and zooming statuses within a controllablerange, and to quickly control the video camera with arbitrary controlvalues without current statuses.

Further, as a maximum image-sensing area image is obtained and displayedwithin the corresponding frame, upon operating the video camera, theoperator can see object(s) within an image-sensing area, which assiststhe operator to operate the video camera, i.e., improves operability.

The present invention can be applied to a system constituted by aplurality of devices (e.g., host computer, interface, reader, printer)or to an apparatus comprising a single device (e.g., copy machine,facsimile).

Further, the object of the present invention can be also achieved byproviding a storage medium storing program codes for performing theaforesaid processes to a system or an apparatus, reading the programcodes with a computer (e.g., CPU, MPU) of the system or apparatus fromthe storage medium, then executing the program.

In this case, the program codes read from the storage medium realize thefunctions according to the embodiments, and the storage medium storingthe program codes constitutes the invention.

Further, the storage medium, such as a floppy disk, a hard disk, anoptical disk, a magneto-optical disk, CD-ROM, CD-R, a magnetic tape, anon-volatile type memory card, and ROM can be used for providing theprogram codes.

Furthermore, besides aforesaid functions according to the aboveembodiments are realized by executing the program codes which are readby a computer, the present invention includes a case where an OS(operating system) or the like working on the computer performs a partor entire processes in accordance with designations of the program codesand realizes functions according to the above embodiments.

Furthermore, the present invention also includes a case where, after theprogram codes read from the storage medium are written in a functionexpansion card which is inserted into the computer or in a memoryprovided in a function expansion unit which is connected to thecomputer, CPU or the like contained in the function expansion card orunit performs a part or entire process in accordance with designationsof the program codes and realizes functions of the above embodiments.

As many apparently widely different embodiments of the present inventioncan be made without departing from the spirit and scope thereof, it isto be understood that the invention is not limited to the specificembodiments thereof except as defined in the appended claims.

What is claimed is:
 1. A camera control apparatus for controlling acamera in which an image-sensing direction and image-sensingmagnification can be arbitrarily controlled from an external device,said camera having a limiter for panning and tilting,comprising:delimiter-display means for displaying a first delimiterindicating a maximum image-sensing area defined by said limiter ofpanning and tilting of said camera, and a second delimiter indicating acurrent image-sensing area, wherein a display position of said seconddelimiter is fixed, and a display position and a size of said firstdelimiter are changed in accordance with a current image-sensingdirection and a current image-sensing magnification so that the displayposition and a size of said second delimiter correspond to the currentimage-sensing direction and its current image-sensing magnification. 2.The camera control apparatus according to claim 1, furthercomprising:operation means for operating said first delimiter displayedby said display means; and control means for controlling theimage-sensing direction and the image-sensing magnification of saidcamera, in accordance with operation of said first delimiter by saidoperation means, such that said first and second delimiters aredisplayed relatively to each other.
 3. The camera control apparatusaccording to claim 1, further comprising second delimiter display meansfor, at a predetermined time, obtaining an image within the maximumimage-sensing area at a current zoom value, while moving said camerawithin a controllable range in an image-sensing direction, anddisplaying the image within said first delimiter.
 4. The camera controlapparatus according to claim 3, wherein the predetermined time is thestart of camera control.
 5. The camera control apparatus according toclaim 3, wherein the predetermined time is when an operator's specificinstruction is inputted.
 6. The camera control apparatus according toclaim 3, wherein the predetermined time is when camera-operation inputis determined.
 7. The camera control apparatus according to claim 1,further comprising:camera-operation area setting means for setting acamera-operation area, inside or peripheral of said first delimiter;operation means for operating the camera-operation area; and controlmeans for updating display of said first delimiter by said displaymeans, and controlling said camera, in accordance with operation of thecamera-operation area by said operation means.
 8. The camera controlapparatus according to claim 7, wherein said control means updates thedisplay position of said first delimiter by said display means, andcontrols said camera, in accordance with a predetermined pointeroperation of said operation means started from inside of thecamera-operation area.
 9. The camera control apparatus according toclaim 7, wherein said control means updates the size of said firstdelimiter by said display means, and controls said camera, in accordancewith a predetermined pointer operation of said operation means startedfrom inside of the camera-operation area.
 10. The camera controlapparatus according to claim 1, wherein said first delimiter isdisplayed so as to indicate the maximum image-sensing area at a currentimage-sensing magnification defined by the limitation on image-sensingdirection.
 11. A camera control apparatus for controlling a camera inwhich at least panning and tilting can be arbitrarily controlled, saidcamera having a limiter for panning and tilting, comprising:displaymeans for displaying a first delimiter indicating a potential maximumimage-sensing area defined by said limiter of panning and tilting ofsaid camera, and a second delimiter indicating a current image-sensingarea, corresponding to current image-sensing conditions, at a positionwithin said first delimiter; and control means for controlling a fieldof view of said camera by panning and tilting said camera in accordancewith a predetermined operation, wherein a central position coordinatesof said first delimiter are fixed, and display of said second delimiteris updated relatively to said first delimiter so that said first andsecond delimiters are displayed in accordance with the currentimage-sensing conditions.
 12. The camera control apparatus according toclaim 11, further comprising operation means for operating said firstdelimiter,wherein said control means controls said camera, in accordancewith relativity of said first delimiter to said second delimiter by saidoperation means.
 13. The camera control apparatus according to claim 11,further comprising second delimiter display means for, at apredetermined time, obtaining an image within the maximum image-sensingarea at a current zoom value, while moving said camera within acontrollable range in an image-sensing direction, and displaying theimage within said first delimiter.
 14. The camera control apparatusaccording to claim 13, wherein the predetermined time is the start ofcamera control.
 15. The camera control apparatus according to claim 13,wherein the predetermined time is when an operator's specificinstruction is inputted.
 16. The camera control apparatus according toclaim 13, wherein the predetermined time is when camera-operation inputis determined.
 17. The camera control apparatus according to claim 11,further comprising operation means including a pointing device such as amouse, for operating a camera-operation area set around said seconddelimiter within said first delimiter,wherein said control means updatesdisplay of said second delimiter and controls said camera, in accordancewith operation by said operation means.
 18. The camera control apparatusaccording to claim 17, wherein said control means updates a displayposition of said first delimiter and controls said camera, in accordancewith a predetermined drag operation of said operation means.
 19. Thecamera control apparatus according to claim 17, wherein said controlmeans updates a display size of said second delimiter and controls saidcamera, in accordance with a predetermined drag operation of saidoperation means.
 20. A camera control apparatus for controlling a camerain which an image-sensing direction can be controlled from an externaldevice, said camera having a limiter for panning and tilting,comprising:first delimiter display means for displaying a firstdelimiter indicating a current image-sensing area of said camera; seconddelimiter display means for displaying a second delimiter indicating animage-sensing enable range defined by said limiter of panning andtilting of said camera; display-position change means for changing adisplay position of said second delimiter based on a predeterminedinstruction; and control means for controlling the image-sensingdirection of said camera in accordance with the predeterminedinstruction.
 21. The camera control apparatus according to claim 20,wherein said camera can be controlled from an external device.
 22. Thecamera control apparatus according to claim 21, furthercomprising:magnification setting means for setting an image-sensingmagnification of said camera; and delimiter-size change means forsetting a size of said second delimiter, in accordance with themagnification set by said magnification setting means.
 23. The cameracontrol apparatus according to claim 22, further comprising:imagegeneration means for generating an image of a wide view by linking aplurality of images obtained by image sensing of said camera whilesequentially updating the image-sensing direction; and image displaymeans for processing image data, corresponding to the image-sensingenable area indicated by said second delimiter, within the imagegenerated by said image generation means, and displaying the image datawithin said second delimiter.
 24. The camera control apparatus accordingto claim 23, wherein said image generation means generates the image ofa wider view by linking images image-sensed at a lowest magnification.25. The camera control apparatus according to claim 26, wherein saidimage display means includes:extraction means for extracting an area ofa size based on the current image-sensing magnification of said camera,from the image generated by said image generation means; andmagnification means for magnifying the area extracted by said extractionmeans, in accordance with the size of said second delimiter.
 26. Thecamera control apparatus according to claim 21, furthercomprising:magnification setting means for setting an image-sensingmagnification of said camera; and delimiter-size change means forsetting a size of said first delimiter, in accordance with themagnification set by said magnification setting means.
 27. The cameracontrol apparatus according to claim 26, further comprising:imagegeneration means for generating an image of a wide view by linking aplurality of images obtained by image sensing of said camera whilesequentially updating the image-sensing direction; and image displaymeans for processing image data, corresponding to the image-sensingenable area indicated by said second delimiter, within the imagegenerated by said image generation means, and displaying the image datawithin said second delimiter.
 28. The camera control apparatus accordingto claim 27, wherein said image generation means generates the image ofwider view by linking images image-sensed at a lowest magnification. 29.The camera control apparatus according to claim 28, wherein said imagedisplay means includes:extraction means for extracting an area of a sizebased on the current image-sensing magnification of said camera, fromthe image generated by said image generation means; and magnificationmeans for magnifying the area extracted by said extraction means, inaccordance with the size of said second delimiter.
 30. A camera controlmethod for controlling an apparatus for controlling a camera in which animage-sensing direction can be controlled from an external device, saidcamera having a limiter for panning and tilting, comprising:a firstdelimiter display step of displaying a first delimiter indicating acurrent image-sensing area of said camera; a second delimiter displaystep of displaying a second delimiter indicating an image-sensing enablerange defined by said limiter of panning and tilting of said camera; adisplay-position change step of changing a display position of saidsecond delimiter in accordance with a predetermined instruction; and acontrol step of controlling the image-sensing direction of said camerain accordance with the predetermined instruction.
 31. The camera controlmethod according to claim 30, wherein said camera can be controlled froman external device.
 32. The camera control method according to claim 30,further comprising:a magnification setting step of setting animage-setting magnification of said camera; and a delimiter-size changestep of changing a size of said second delimiter, in accordance with themagnification set at said magnification setting step.
 33. The cameracontrol method according to claim 32, further comprising:an imagegeneration step of generating an image of a wide view by linking aplurality of images obtained by image sensing of said camera whilesequentially updating the image-sensing direction; and an image displaystep of processing image data, corresponding to the image-sensing enablearea indicated by said second delimiter, within the image generated atsaid image generation step, and displaying the image data within saidsecond delimiter.
 34. The camera control method according to claim 33,wherein at said image generation step, the image of a wider view isgenerated by linking images image-sensed at a lowest magnification. 35.The camera control method according to claim 34, wherein said imagedisplay step includes:an extraction step of extracting an area of a sizebased on the current image-sensing magnification of said camera, fromthe image generated at said image generation step; and a magnificationstep of magnifying the area extracted at said extraction step, inaccordance with the size of said second delimiter.
 36. The cameracontrol method according to claim 30, further comprising:a magnificationsetting step of setting an image-setting magnification of said camera;and a delimiter-size change step of changing a size of said firstdelimiter, in accordance with the magnification set at saidmagnification setting step.
 37. The camera control method according toclaim 36, further comprising:an image generation step of generating animage of a wide view by linking a plurality of images obtained by imagesensing of said camera while sequentially updating the image-sensingdirection; and an image display step of processing image data,corresponding to the image-sensing enable area indicated by said seconddelimiter, within the image generated at said image generation step, anddisplaying the image data within said second delimiter.
 38. The cameracontrol method according to claim 37, wherein at said image generationstep, the image of wider view is generated by linking imagesimage-sensed at a lowest magnification.
 39. The camera control methodaccording to claim 38, wherein said image display step includes:anextraction step of extracting an area of a size based on the currentimage-sensing magnification of said camera, from the image generated atsaid image generation step; and a magnification step of magnifying thearea extracted at said extraction step, in accordance with the size ofsaid second delimiter.
 40. A computer product constructed by a storagemedium holding program codes for controlling a camera in which animage-sensing direction can be controlled from an external device, saidcamera having a limiter for panning and tilting,comprising;first-delimiter display process program codes for displayinga first delimiter indicating a current image-sensing area of saidcamera; second-delimiter display process program codes for displaying asecond delimiter indicating an image-sensing enable range defined bysaid limiter of panning and tilting of said camera; display-positionchange process program codes for changing a display position of saidsecond delimiter in accordance with a predetermined instruction; andcontrol process program codes for controlling the image-sensingdirection of said camera in accordance with the predeterminedinstruction.
 41. A camera control apparatus for controlling a camera inwhich an image-sensing direction and image-sensing magnification can bearbitrarily controlled from an external device,comprising:delimiter-display means for displaying a first delimiterindicating a maximum image-sensing area which is defined by a limit ofpanning and tilting and exceeding a current image-sensing range of saidcamera, and a second delimiter indicating the current image-sensing areaof said camera, wherein a display position of said second delimiter isfixed, and a display position and a size of said first delimiter arechanged in accordance with a current image-sensing direction and acurrent image-sensing magnification so that the display position and asize of said second delimiter correspond to the current image-sensingdirection and the current image-sensing magnification.
 42. The cameracontrol according to claim 41, further comprising:operations means foroperating said first delimiter displayed by said display means; andcontrol means for controlling the image-sensing direction and theimage-sensing magnification of said camera, in accordance with operationof said first delimiter by said operation means, such that said firstand second delimiters are displayed relatively to each other.
 43. Thecamera control apparatus according to claim 41, further comprisingsecond delimiter display means for, at a predetermined time, obtainingan image within the maximum image-sensing area at a current zoom value,while moving said camera within a controllable range in an image-sensingdirection, and displaying the image within said first delimiter.
 44. Thecamera control apparatus according to claim 43, wherein thepredetermined time is the start of camera control.
 45. The cameracontrol apparatus according to claim 43, wherein the predetermined timeis when an operator's specific instruction is inputted.
 46. The cameracontrol apparatus according to claim 43, wherein the predetermined timeis when camera-operation input is determined.
 47. The camera controlapparatus according to claim 41, further comprising:camera-operationarea setting means for setting a camera-operation area, inside orperipheral of said first delimiter; operation means for operating thecamera-operation area; and control means for updating display of saidfirst delimiter by said display means, and controlling said camera, inaccordance with operation of the camera-operation area by said operationmeans.
 48. The camera control apparatus according to claim 47, whereinsaid control means updates the display position of said first delimiterby said display means, and controls said camera, in accordance with apredetermined pointer operation of said operation means started frominside of the camera-operation area.
 49. The camera control apparatusaccording to claim 47, wherein said control means updates the size ofsaid first delimiter by said display means, and controls said camera, inaccordance with a predetermined pointer operation of said operationmeans started from inside of the camera-operation area.
 50. The cameracontrol apparatus according to claim 41, wherein said first delimiter isdisplayed so as to indicate the maximum image-sensing area at a currentimage-sensing magnification.
 51. A camera control apparatus forcontrolling a camera in which at least panning and tilting can bearbitrarily controlled; comprising:display means for displaying a firstdelimiter indicating a potential maximum image-sensing area defined bylimitations on panning and tilting and exceeding a current image-sensingarea of said camera, and a second delimiter indicating the currentimage-sensing area of said camera, corresponding to currentimage-sensing conditions, at a position within said first delimiter; andcontrol means for controlling a field of view of said camera by panningand tilting said camera in accordance with a predetermined operation,wherein a central position coordinates of said first delimiter arefixed, and display of said second delimiter is updated relatively tosaid first delimiter so that said first and second delimiters aredisplayed in accordance with the current image-sensing conditions. 52.The camera control apparatus according to claim 51, further comprisingoperation means for operating said first delimiter,wherein said controlmeans controls said camera, in accordance with relativity of said firstdelimiter to said second delimiter by said operation means.
 53. Thecamera control apparatus according to claim 51, further comprisingsecond delimiter display means for, at a predetermined time, obtainingan image within the maximum image-sensing area at a current zoom value,while moving said camera within a controllable range in an image-sensingdirection, and displaying the image within said first delimiter.
 54. Thecamera control apparatus according to claim 53, wherein thepredetermined time is the start of camera control.
 55. The cameracontrol apparatus according to claim 53, wherein the predetermined timeis when an operator's specific instruction is inputted.
 56. The cameracontrol apparatus according to claim 53, wherein the predetermined timeis when camera-operation input is determined.
 57. The camera controlapparatus according to claim 51, further comprising operation meansincluding a pointing device such as a mouse, for operating acamera-operation area set around said second delimiter within said firstdelimiter,wherein said control means updates display of said seconddelimiter and controls said camera, in accordance with operation by saidoperation means.
 58. The camera control apparatus according to claim 57,wherein said control means updates a display position of said firstdelimiter and controls said camera, in accordance with a predetermineddrag operation of said operation means.
 59. The camera control apparatusaccording to claim 57, wherein said control means updates a display sizeof said second delimiter and controls said camera, in accordance with apredetermined drag operation of said operation means.